Motion and multiple video cards

I'm on the verge of purchasing a Mac Pro, I've done some research and it seems the ATI Radeon X1900 XT is by far the best graphics card for Motion and other programs that utilize the GPU. Now, unfortunately these cards are no longer an option when you configure a system.

My question is if I choose one of the standard video cards and run two monitors off that, and install a X1900, will Motion use the X1900, or will it tend to default to the graphics card powering the monitors? (resulting in slower renders/previews/etc).

I've looked around and haven't been able to really find an answer, so I was hoping you guys would be able to help. Thanks!

Motion uses the GPU that is driving your main display, which is the monitor that has the main menu bar on it (File, Edit, View, etc).

The X1900 is a great card (I have one), but I'd highly recommend getting the ATI Radeon 3870. It's not sold by Apple, but you can get it from Mac resellers like Small Dog. You can see Motion benchmarks for the 3870 here.

It's cheap and a generation newer than the X1900. I'd get the cheapest stock card in your Mac Pro and drop in the 3870 as your primary GPU.

I've got another question, which may be suited more for the OS X forum...

Browsing NewEgg for the 3870 comes up with quite a few different options. They all use the 3870 chipset, just with varying clock speeds and memory. Is it more the chipset that's supported in OS X or the general configuration of the card?

I'm assuming only the card you linked to will work, but if anyone know's differently, there's some beastly cards running on the 3870 chipset out there ;)

Googling the card turned up a long list of bizarre configurations of the 3870 chipset. How the heck is anyone supposed to know which one is best for Motion, Aperture, or the future FCP7?
The Macintosh version appears to have a blue heatsink/fan. maybe these REviews might help but most are PC- and game-centric.

If you look at the links in my post, you'll see that I linked to the ATI product page which identifies it as the "Mac & PC Edition". As I mentioned, it's only being sold by Apple resellers, so far, like Small Dog and Other World Computing.

Somewhere between $150 and $3,000, "best" and "affordable" become blurry or mutually exclusive. AFAICT, this card is way over the top, provides far more technology than Motion can even understand and can't take advantage of.
Searching Google for real world reviews of this behemoth inside a Mac turned up blank. I'm beginning to think no one has ever really bought one.

The apple site sez this:

All-new high-performance graphics cards from ATI and NVIDIA make Mac Pro graphics technology even more cutting edge. The standard graphics card — an ATI Radeon HD 2600 XT with 256MB of GDDR3 memory, PCI Express 2.0, and two dual-link DVI ports — provides great performance for typical creative applications. And you get dual 30-inch Apple Cinema HD Display support out of the box.For motion graphics, 3D modeling, rendering, or animation, you’ll need the greater graphics horsepower offered by the NVIDIA GeForce 8800 GT with 512MB of GDDR3 memory and latest-generation NVIDIA GPU technology. The optional NVIDIA Quadro FX 5600 graphics card is the ultimate workstation-class graphics card available, with a massive 1.5GB of GDDR3 memory and a 3D stereo port for stereo-in-a-window applications. All of these cards feature the latest-generation unified shader model support. Compared to dedicated pixel and vertex shaders, shaders are no longer special-purpose and can now be utilized based on the needs of the graphics application.

bogiesan

This is my standard sigfile so do not take it personally: "For crying out loud, read the freakin' manual."